Monday, June 18, 2018

[PaleoOrnithology • 2018] Panraogallus hezhengensis • Vocal Specialization through Tracheal Elongation in An Extinct Miocene Pheasant from China

Panraogallus hezhengensis 
Li, Clarke, Eliason, Stidham, Deng & Zhou, 2018

Modifications to the upper vocal tract involving hyper-elongated tracheae have evolved many times within crown birds, and their evolution has been linked to a ‘size exaggeration’ hypothesis in acoustic signaling and communication, whereby smaller-sized birds can produce louder sounds. A fossil skeleton of a new extinct species of wildfowl (Galliformes: Phasianidae) from the late Miocene of China, preserves an elongated, coiled trachea that represents the oldest fossil record of this vocal modification in birds and the first documentation of its evolution within pheasants. The phylogenetic position of this species within Phasianidae has not been fully resolved, but appears to document a separate independent origination of this vocal modification within Galliformes. The fossil preserves a coiled section of the trachea and other remains supporting a tracheal length longer than the bird’s body. This extinct species likely produced vocalizations with a lower fundamental frequency and reduced harmonics compared to similarly-sized pheasants. The independent evolution of this vocal feature in galliforms living in both open and closed habitats does not appear to be correlated with other factors of biology or its open savanna-like habitat. Features present in the fossil that are typically associated with sexual dimorphism suggest that sexual selection may have resulted in the evolution of both the morphology and vocalization mechanism in this extinct species.

Systematic paleontology
AVES Linnaeus, 1758
GALLIFORMES Linnaeus, 1758

PHASIANIDAE Vigors, 1825

Panraogallus hezhengensis gen et sp. nov.

Etymology: The genus name is the pinyin of the Chinese characters meaning ‘coiling’ and the Latin for ‘chicken,’ referring to the preserved elongate trachea in this species. The specific epithet, ‘hezhengensis’ refers to Hezheng area in the Linxia Basin of Gansu Province where abundant fossils, including the holotype, have been collected.

Specimen number: HMV 1876 (HMV, Hezheng Paleozoological Museum, Vertebrate Collection, Gansu Province, China).

Locality and age: Baihua area near Zhuangkeji Township, Guanghe County, Gansu Province, China exposes the Liushu Formation that is late Miocene (7.25–11.1 Ma).

Fig.1 Type specimen of Panraogallus hezhengensis (HMV 1876). It has coiled, super-elongated windpipe and lived in the late Miocene of Gansu Province in northwest China (Photo by Z. LI and reconstruction by X. GUO at IVPP)

Zhiheng Li, Julia A. Clarke, Chad M. Eliason, Thomas A. Stidham, Tao Deng and Zhonghe Zhou. 2018. Vocal Specialization through Tracheal Elongation in An Extinct Miocene Pheasant from China. Scientific Reports. 8, Article number: 8099. DOI: 10.1038/ncomms12739

Song From The Distant Past, A New Fossil Pheasant From China Preserves A Super-Elongated Windpipe
Song from the distant past, a new fossil pheasant from China preserves a super-elongated windpipe via @physorg_com
Song from the distant past, a new fossil pheasant from China preserves a... via @EurekAlert
El esqueleto fosilizado de un faisán con una tráquea súper larga via @natgeoesp

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